Automatic lock for dumbwaiters



Feb. 4, 1936. 2,029,867

S. HALMI AUTOMATIC LOOK FOR DUMB-WAITERS Filed March 6, 1935 INVENTOR STEVE HALMI BYWW ATTORNEY Patented Feb. 4, 1936 UNITED STATES PATENT OFFICE 2,029,867 AUTOMATIC LOCK FOR'DUMBWAITERS Steve Halmi, New York, N. Y. Application March 6, 1935, Serial No. 9,598 4 Claims. (01. 187-61) This invention relates to new and useful improvements in an automatic lock for dumbwaiters.

The invention has for an object the construction of a device as mentioned which is used in combination with a dumbwaiter shaft and car, and arranged in such a manner as to lock the doors of the shaft except when the dumbwaiter car is immediately behind any door, in which case, only that particular door is unlatched.

Still further the invention contemplates the mounting of self-closing locks on the door jambs or other stationary portions of the dumbwaiter shaft, and mechanism on the dumbwaiter car adapted to open the locks selectively as the dumbwaiter assumes a position behind the doors.

Furthermore, the invention contemplates the provision of an acoustic device for sounding when the dumbwaiter car has assumed a position behind any of the doors.

Another object of the invention is the construction of a device as mentioned which is simple and durable and which can be manufactured and sold at a reasonable cost.

For further comprehension of the invention,

and of the objects and advantages thereof, reference will be had to the following description and accompanying drawing, and to the appended claims in which the various novel features of the invention are more particularly set forth.

In the accompanying drawing forming a material part of this disclosure:-

Fig. 1 is a vertical sectional view of a portion of a dumbwaiter shaft and car, and automatic locks according to this invention, this view being taken on the line I--I of Fig. 4.

Fig. 2 is a horizontal sectional view taken on the line 2-2 of Fig. 1.

Fig. 3 is a perspective view of the dumbwaiter car and the automatic self-closing lock of the shaft door.

Fig. 4 is a fragmentary enlarged detailed view of a portion of Fig. 2 showing the lock in greater detail.

Fig. 5 is a fragmentary sectional view taken on the line 55 of Fig. 4.

ig. 6 is a side elevational view of the cam which is mounted on the dumbwaiter car, and schematic wiring of the acoustic device.

Fig. 7 is a view similar to Fig. 6 but illustrating another embodiment of the invention.

The automatic lock for dumbwaiters, according to this invention, is used in combination with a dumbwaiter car ill operating in a dumbwaiter shaft II. The shaft ll extends through several stories of a building. Numeral l2 indicates a floor section. Numerals l3 indicate doors at different locations in the dumbwaiter shaft. With each of the doors I3 is associated automatic selfclosing latches, hereafter more fully described. A means is mounted on the dumbwaiter car for 5 rendering anyone of said latches inoperative as the dumbwaiter car assumes a position behind the particular door.

Each automatic lock comprises a bracket l4 which is attached upon the door jamb l3 of 10 the door l3. The bracket I4 is formed with a cylindrical bowl portion l5 which supports a cylindrical member IS. The cylindrical member I6 is formed withdiametrically opposite arm I! and bolt I8 projecting through openings in 15 the sides of the cylindrical member l5. A stud 19 projects from the bracket l4 coaxial in the cylindrical portion IS. A spring 20 is coaxially arranged on the stud l9 and has one of its ends 20 attached upon the stud and the other end 20 20 on the cylindrical member 16 tending to urge the latter into a certain position.

This position is one in which the bolt l8 engages a keeper 2| which is attached on the door l3. The keeper 2| and bolt l8 are formed with inter- 25 engageable hooks as clearly seen in Fig. 4. The dot and dash lines in Fig. 4 indicate a moved position of the parts l6, l1 and I8, in which the latch is open.

The means for rendering the latch inoperative 30 comprises a cam 23 mounted on the dumbwaiter car ID. This cam 23 is formed with an arcuate cam surface 23' adapted to engage against the projection l1 to move the projection as the dumbwaiter passes to a position in which the latch is 35 open. The cam surface 23 rises until a central area 23 and then falls from this area. The arrangement is such that as the dumbwaiter car assumes its position behind the door, the latch is opened, and as it moves past this position, the latch is released so that it automatically closes.

Fig. 3 is a schematic perspective view. It should be understood that the keeper 2| is attached upon the door l3, which is not shown in 45 this view. Furthermore, that the bracket I4 is attached upon the door jamb, also not shown.

The dumbwaiter car In is formed with an open front Ill partially closed along one side by an angle iron 25. This angle iron is arranged so 50 that one arm 25' extends over and covers the cam 23. Consequently, when the door [3 is open, the cam and the latch are partially hid from view and protected against tinkering. A disc 28 is engaged over the Open end of the cylindrical 55 member l5 and held in stationary position by a screw 29 which threadedly engages the stud l9 so as to engage the spring 20.

A wheel I7 is rotatively secured at the extremity of projection I1 and engages the surface of the angle iron 2 An acoustic means is provided for indicating when the dumbwaiter car is at its proper position of rest behind anyone of the doors. This acoustic device is mounted on the dumbwaiter car itself. It comprises an electric bell 30 or other acoustic device connected in circuit with a source of power 3| and a switch consisting of a pair of contacts 32 mounted on the cam 23 and spaced from each other and adapted to be connected by a bridge element 33 mounted on the projection I 1.

In Fig. 7 another embodiment of the invention has been disclosed where there is a mechanical acoustic device. This device consists of a plurality of serrations 34 formed upon the high portion of the cam 23 and adapted to make sufficient noise in combination with the projection I 1 as the latter assumes its position to announce the dumbwaiter.

The operation of the device is as follows:-

The dumbwaiter car I0 is equipped to be moved up and down in the shaft in any conventional manner. Since this does not form a portion of the invention it is not disclosed or described in detail. As the dumbwaiter car l0 assumes a position behind each door l3, the latch holding the door closed will be automatically opened. The reason for this is that the cam 23 will move the projection l! which is connected to move the bolt I 8 free from the keeper 2|. A person may now open the dumbwaiter door and use the dumbwaiter.

While I have illustrated and described the preferred embodiment of my invention, it is to be understood that I do not limit myself to the precise construction herein disclosed and the right is reserved to all changes and modifications coming within the scope of the invention as defined in the appended claims.

Having thus described my invention, what I claim as new, and desire to secure by United States Letters Patent is:-

1. In conjunction with a dumbwaiter car operating in a dumbwaiter shaft having doors in difurging said bolt into engagement with a keeper mounted on the door, a projection from the bolt, a cam upon the dumbwaiter car engageable with said projection to move the bolt into an inoperative position, and an angle iron mounted on said dumbwaiter car and arranged with one of its arms extending across said cam to shield the cam when the door is opened.

2. In conjunction with a dumbwaiter car operating in a dumbwaiter shaft having doors in different elevations, an automatic closing latch for each door comprising a bracket mounted on the material of the dumbwaiter shaft, a pivotally mounted bolt upon the bracket, resilient means urging said bolt into engagement with a keeper mounted on the door, a projection from the bolt, a cam upon the dumbwaiter car engageable with said projection to move the bolt into an inoperative position, said bracket being formed with a cylindrical portion, a cylindrical member mounted within said cylindrical portion and provided with projections, one of said projections comprising the bolt, and the other of said projections being the operator for the bolt.

3. In conjunction with a dumbwaiter car operating in a dumbwaiter shaft having doors in different elevations, an automatic closing latch for each door comprising a bracket mounted on the material of the dumbwaiter shaft,

urging said bolt into engagement with a keeper mounted on the door, a projection from the bolt, a cam upon the dumbwaiter car cngageable with said projection to move the bolt into an inoperative position, said bracket being formed with a cylindrical portion, a cylindrical member mounted within said cylindrical portion and provided with projections, one of said projections comprising the bolt, and. the other of said projections being the operator for the bolt, and a spring mounted within the inner cylindrical member and acting between said cylindrical member and a stationary stud on said bracket.

4. In conjunction with a dumbwaiter car operating in a dumbwaiter shaft having doors in different elevations, an automatic closing latch for each door comprising a bracket mounted on the material of the dumbwaiter mounted bolt upon the bracket, urging said bolt into engagement with a keeper mounted on the door, a projection from the bolt, a cam upon the dumbwaiter car engageable with said projection to move the bolt into an inoperative position, said bracket being formed with a cylindrical portion, a cylindrical member mounted within said cylindrical portion and provided with projections, one of said projections comprising the bolt, and the other of said projections being the operator for the bolt, and a spring mounted within the inner cylindrical member and acting between said cylindrical member and a stationary stud on said bracket, and a disc mounted on said stationary stud and extending over the inner cylindrical member for encasing the same.

STEVE HALMI. 

